Bash tab completion for argparse.

Tab complete all the things!

Argcomplete provides easy, extensible command line tab completion of
arguments for your Python script.

Argcomplete is particularly useful if your program has lots of options
or subparsers, and if your program can dynamically suggest completions
for your argument/option values.

Note: You need to run (as root) 'activate-global-python-argcomplete'
script once you install this package.
